Changed it to NSCalendarIdentifierIslamic not working

[shoaibhassanWhizpool]

I changed it type to islamic in viewDidLoad of subclass of CKCalendarViewController.

here is my code

NSCalendar *islamicCalender = [[NSCalendar alloc] initWithCalendarIdentifier:NSCalendarIdentifierIslamic];
[self.calendarView setCalendar:islamicCalender];
[self.calendarView reload];

but it does't allow me to update after 2 times right button pressed for next month.and it stucks.